Python疑难杂症--考试复习

1.排序输出字典中数据 

dic1 = {'Tom':21,'Bob':18,'Jack':23,'Ana':20}
dic2 = {'李雷':21,'韩梅梅':18,'小明':23,'小红':20}
n=int(input())
if n>len(dic1):n=len(dic1)
print(sorted(dic1.keys())[:n])
print(sorted(dic2.items(),key=lambda item:item[1])[:n])

 2.罗马数字转换

def F(s):d={'I':1,'V':5,'X':10,'L':50,'C':100,'D':500,'M':1000,'IV':3,'IX':8,'XL':30,'XC':80,'CD':300,'CM':800}t=0 for i in range(len(s)):if s[i-1:i+1] in d:t+=d[s[i-1:i+1]]else:t+=d[s[i]]return t s=input()
print(F(s))

 3.模拟用户登录

username in 

user_table={'Kate':'xxy123','RRAj':'45desx','admin':'ie1234','Rose':'89dkyx12'}
c=0
while c<3:username=input()password=input()if username in user_table.keys() and password==user_table[username]: # username 用inprint("登录成功")breakelse:print('登录失败,请重新输入!')

 4.特殊回文数

 

#逆序
def R(s):return int(str(s)[::-1])#求和
def S(s):return sum([int(i) for i in str(s)])n=int(input())
flag=0
if n<1 or n>54:print("输入错误，请重新输入！")
else:for j in range(10000,1000000):if R(j)==j and S(j)==n:print(j)flag=1if flag==0:print("无满足条件的数！")